Systems and methods for manufacturing orthopedic prostheses

ABSTRACT

An orthopedic prosthesis mold, comprising a first housing including a first cavity therein shaped to form a portion of an orthopedic prosthesis; a second housing coupled to the first housing, the second housing including a second cavity therein shaped to form a portion of an orthopedic prosthesis, wherein the first and second housings are constructed from a material having a first hardness; a first shell element configured to receive at least a portion of the first housing therein; a second shell element configured to receive at least a portion of the first housing therein, wherein the first and second shell elements are constructed from a material having a second hardness greater than the first hardness; and a connection element releasably engageable to the first and second shell elements to prevent separation of the first shell element from the second shell element.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part-of patent application Ser.No. 16/990,490, filed Aug. 11, 2020, entitled SYSTEMS AND METHODS FORMANUFACTURING ORTHOPEDIC PROSTHESES, the entirety of which isincorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

N/A

FIELD OF THE INVENTION

The present disclosure relates to orthopedic prostheses and methods andsystems for the manufacture thereof.

BACKGROUND OF THE INVENTION

A healthy knee joint is able to withstand great forces that are exertedas the knee flexes and extends and supports the weight of the body.However, when the knee joint becomes diseased, damaged or is otherwiseunable to withstand the forces required of that joint, it may becomenecessary to reconstruct or replace the knee joint. When replacement isnecessary, the natural knee joint is replaced with a prosthetic kneejoint. A typical knee joint prosthesis includes a femoral component anda tibial component. During a replacement knee surgery, portions of boththe tibia and femur are typically resected to allow the placement ofprosthetic tibial and femoral components, which are anchored to therespective bones.

Sometimes, a small percentage of patients who undergo a total kneereplacement surgery suffer from infections in the knee joint at thesurgical site. To alleviate the effects of the infection, a two-stagerevision of the failed knee replacement is employed. First, the failedprosthesis must be surgically removed and the site debrided and cleansedextensively in order to rid the site of the infection. Before a new,permanent prosthesis can be placed in the old surgical site, the sitemust be free of infection. A temporary antibiotic-impregnated cementspacer may be used as part of the therapy to rid the site of infection.Disinfecting the site of infection may take between 6-8 weeks and up to3-4 months in most circumstances. It is thus common for surgeons toreplace the old prosthetic knee with a temporary implant, typically madeof bone cement, during the 6-8 week period while the infection iscleared up and before the new prosthesis is surgically implanted. Thesecond and final step requires a separate revision surgery to thenreplace the temporary implant with a permanent prosthetic implant.

In the past, surgeons have been left to their own devices when formingcement implants, including the use of negative molds. The process ofmaking a negative mold consists of the surgeon creating a mold byinserting a portion of bone cement into a bowl or other mixing containerand allowing the cement to nearly cure. Prior to complete curing of thebone cement, the surgeon inserts the articulating end of the femoralcomponent into the bone cement to create a mold. Using that mold, thesurgeon then applies an oil to the mold creating a barrier forseparating the cement implant from the cement mold. After applying theoil, cement may be poured into the mold allowing it cure, after whichthe surgeon attaches the resulting bone cement implant onto the femur asa temporary replacement.

Other methods used in the past of forming temporary implants includesurgeons creating the implant with their own hands or simply putting ablock of cement between the tibia and the femur to act as a spacer.However, there are many problems associated with such methods anddesigns, namely increased surgical time due to the preparation andformation time needed for creating the implant. Particular problemsassociated with the block or spacer method include completelyimmobilizing the knee in an extended position, after surgery, for theentire 6-8 week period, which in turn leads to soft tissue damage andfurther complicates the revision surgery. Therefore, reproducing theknee joint using temporary implants that simulate the natural tibial andfemoral components of the knee joint is much more desirable because itpermits the patient to move his/her leg through a minimal range ofmotion. The range of motion, while limited, significantly increases thepatient's comfort over the 6-8 week period allowing the patient to bendhis/her knee for sitting in a chair or for riding in a car and alsoincreases the ease of the revision surgery because the soft tissue hasnot been damaged to the same extent as when the knee is completelyimmobilized.

Attempts have been made in the prior art to provide alternatives tosurgeons creating their own negative molds or even molding a temporaryimplant by hand, including the use of pre-made, disposable molds. Suchattempts include several drawbacks, however. For example, there may be aneed for many different sized molds to accommodate the differences insize from patient to patient. Existing molds are prone to overfillingand spillage, leading to wasted materials and a messy work area.Further, some molds require a surgeon cut the mold to remove it from theimplant once cured. This scoring separation can be quite cumbersome toachieve, can result in small, contaminating particles or pieces of themold or molded prosthesis being strewn about, as well as increasing thelikelihood that the molded prosthesis itself is inadvertently cut ordamaged in the process. Additionally, when a mold is filled with acurable material to make the prosthesis, the pressure inside the moldcan cause the mold itself (and thus the resulting prosthesis) to deform.

In view of these drawbacks, it is desirable to provide orthopedicprosthesis molds and methods of use thereof that safeguard againstoverfilling, spillage and deformation, are easily separable to revealthe molded prosthesis, and provide an accurate, selectable range ofmolded prosthesis sizes.

SUMMARY OF THE INVENTION

The present disclosure advantageously provides an orthopedic prosthesismold, comprising: a first housing including a first cavity thereinshaped to form a portion of an orthopedic prosthesis; a second housingcoupled to the first housing, the second housing including a secondcavity therein shaped to form a portion of an orthopedic prosthesis,wherein the first and second housings are constructed from a materialhaving a first hardness; a first shell element configured to receive atleast a portion of the first housing therein; a second shell elementconfigured to receive at least a portion of the first housing therein,wherein the first and second shell elements are constructed from amaterial having a second hardness greater than the first hardness; and aconnection element releasably engageable to the first and second shellelements to prevent separation of the first shell element from thesecond shell element. The first and second housings may be constructedfrom a material having a hardness between Shore 40A and 80A. The firstand second shell elements may be constructed from a material having ahardness between Shore 40D and 80D. The first and second housings mayalign with and attach to one another along a first axis, and the firstand second shell elements may align with and attach to one another alonga second axis that is not parallel to the first axis.

At least one of the first and second cavities may define an anteriorportion and a posterior portion shaped to form a femoral knee jointprosthesis. At least one of the first and second cavities may be shapedto form a tibial knee joint prosthesis. The orthopedic prosthesis mayinclude a plurality of spacing elements positionable within the secondcavity of the second housing configured to selectively adjust a heightof a prosthesis molded therein. At least one of the first and secondcavities may be shaped to form a hip head prosthesis. At least one ofthe first and second cavities may be shaped to form a hip stemprosthesis, and may include a stem insert defining a porous latticestructure in a portion thereof.

The first housing may define an injection port. The orthopedicprosthesis mold may include an injection port cap releasably engageablewith the injection port to seal the injection port. The first housingmay define a plurality of vent ports.

The first housing may define a groove circumscribing the first cavity,and the second housing may define a protruding wall circumscribing thesecond cavity, the wall being insertable into the groove. The first andsecond shell elements may be substantially cylindrical. The connectionelement may include a threaded lock ring engaging circumferentiallythreaded segments of the first and second shell elements.

The first and second housings may each define one or more longitudinalgrooves in exterior surfaces thereof, wherein the first and second shellelements each define one or more protruding ribs on interior surfacesthereof, and wherein the protruding ribs are positionable in thelongitudinal grooves.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present disclosure, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is an illustration of an example of a femoral-knee orthopedicmold constructed in accordance with the present disclosure;

FIG. 2 is an exploded assembly illustration of the femoral-kneeorthopedic mold of FIG. 1;

FIG. 3 is a top perspective view of an example of a first mold housingof the femoral-knee orthopedic mold of FIG. 1;

FIG. 4 is a bottom perspective view of the first mold housing of FIG. 3;

FIG. 5 is a top view of an example of a second mold housing of thefemoral-knee orthopedic mold of FIG. 1;

FIG. 6 is a top perspective view of the second mold housing of FIG. 5;

FIG. 7 is a bottom perspective view of the second mold housing of FIG.5;

FIG. 8 is an illustration of an example of a tibial-knee orthopedic moldconstructed in accordance with the present disclosure;

FIG. 9 is an exploded assembly illustration of the tibial-kneeorthopedic mold of FIG. 8;

FIG. 10 is a top perspective view of an example of a first mold housingof the tibial-knee orthopedic mold of FIG. 8;

FIG. 11 is a bottom perspective view of the first mold housing of FIG.10;

FIG. 12 is a top view of an example of a second mold housing of thetibial-knee orthopedic mold of FIG. 8;

FIG. 13 is a bottom perspective view of the second mold housing of FIG.12;

FIG. 14 is an illustration of an example of a prosthesis mold insertconstructed in accordance with the present disclosure;

FIG. 15 is an illustration of an example of a spacing elementconstructed in accordance with the present disclosure;

FIG. 16 is an illustration of an example of a hip head orthopedic moldconstructed in accordance with the present disclosure;

FIG. 17a is an exploded assembly illustration of the hip head orthopedicmold of FIG. 16;

FIG. 17b is an exploded assembly illustration of another example of ahip head orthopedic mold;

FIG. 18 is a top perspective view of an example of a first mold housingof the hip head orthopedic mold of FIG. 16;

FIG. 19 is a bottom perspective view of the first mold housing of FIG.18;

FIG. 20 is a top view of an example of a second mold housing of the hiphead orthopedic mold of FIG. 61;

FIG. 21 is a cross-sectional view of the second mold housing of FIG. 20;

FIG. 22 is an illustration of an example of a hip stem orthopedic moldconstructed in accordance with the present disclosure;

FIG. 23 is an exploded assembly illustration of the hip stem orthopedicmold of FIG. 22;

FIG. 24 is a perspective view of an example of a first mold housing ofthe hip stem orthopedic mold of FIG. 22;

FIG. 25 is a perspective view of an example of a second mold housing ofthe hip stem orthopedic mold of FIG. 22;

FIG. 26 is a perspective view of an example of a prosthesis insert for ahip stem orthopedic mold; and

FIG. 27 is a perspective view of an example of a molded prosthesis kitconstructed in accordance with the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides orthopedic prosthesis molds and methodsof use thereof that safeguard against overfilling, spillage anddeformation, are easily separable to reveal the molded prosthesis, andprovide an accurate, selectable range of molded prosthesis sizes. Thefeatures disclosed herein provide prosthesis molds that can withstandconsiderable expansion forces and pressures occurring during use, whichcan range as high as 80 psi to 100 psi within the mold cavities.Referring now to the drawing figures in which like referencedesignations refer to like elements, an example of a femoral orthopedicprosthesis mold assembly constructed in accordance with principles ofthe present invention is shown in FIGS. 1-7 and generally designated as“100.”

The mold assembly 100 generally includes a first housing or body 102 anda second housing or body 104 releasably engageable with the firsthousing. The first and second housings define cavities therein sized andshaped to produce an orthopedic prosthesis, such as that of a femoraland/or tibial knee joint component. For example, the first housing 102may define or include a first cavity 106 therein for receiving a curablematerial to be formed or shaped into at least a portion of an orthopedicprosthesis. The second housing 104 may include a second cavity 108 forreceiving a curable material to be formed or shaped into at least aportion of an orthopedic prosthesis. The second cavity 108 may bepositional adjacent to and/or substantially congruous with the firstcavity 106 when the first and second housings are engaged or coupled toone another to cooperatively from a substantially continuous prosthesis.

In the illustrated example, the first and second cavities 106, 108 ofthe first and second housings 102, 104 of the assembly 100 may be usedto manufacture a femoral prosthesis for a knee joint. To form such aprosthesis, the first and second cavities 106, 108 each include ananterior portion 110 and a posterior portion 112 sized and shaped toform the resulting features of the prosthesis. The first and secondhousings 102, 104 of the assembly 100 shown in FIGS. 1-7 is illustratedas a femoral prosthesis mold, but it is also contemplated that thefeatures described herein may be provided for a mold sized and shaped toform a tibial component of a knee joint, or other orthopedic prostheses.

The first and second housings 102, 104 may define one or more grooves,detents, lips, or other mating features complimentary to each other toaid in aligning and/or securing the components to one another, and tofurther resist separation when under pressure from injection of materialinto the mold and/or expansion or curing of an injected material. Forexample, as shown in FIG. 4, the first housing 12 may define aprotrusion 118 on its lower end that is complementary and securelypositionable within a groove or well 120 in the second housing 104. Thefirst housing 102 may include or define a recessed groove 122circumscribing or otherwise routing along the interior cavity 106, withthe second housing 104 defining a complementary wall or protruding rib124 circumscribing or otherwise routing around the interior cavity 106that is securable in the groove 122. Providing such matable lock-and-keyfeatures provides increased resistance to separation between thehousings, as well as reducing the likelihood of leakage at the couplingpoints between the first and second housings.

The first housing 102 may define an injection opening 126 incommunication with the interior cavity 106 to allow the first and secondhousings 102, 104 to be filled with a curable material to form aprosthesis. An injection opening cap or cover 128 may also be included.The injection opening cap 128 may include a stamping component orindicia that imprints the injected molding material within the first andsecond cavities prior to curing. This allows the resulting prosthesis tohave custom markings identifying the patient, infused pharmacologicalinformation, traceability information (lot number, manufacturing date,etc.), or the like. The injection cap 128 may further include a cuttingsurface or edge to remove, debride, or otherwise remove excess portionsof the molded prosthesis once its cured. The first housing 102 mayfurther define one or more vents 130 in an upper surface thereof toallow air pockets to escape, as well as provide an exit or spillway forexcess material.

The first and second housings 102, 104 may be constructed from a polymerincluding one or more rubber or silicone components, and may have adurometer or hardness between Shore 40A and 80A. The first and secondhousings may provide a desired degree of pliability to facilitateremoving a molded prosthesis from the interior cavities of the first andsecond housings.

The mold assembly 100 may include an exterior casing or shell that isreleasably engageable to, and at least partially encompassing of, thefirst and second housings 102, 104 to secure the overall assembly andposition of the first and second housings relative to one another duringuse. For example, the assembly 100 may include a first shell element 132and a second shell element 134 that are releasably engageable to oneanother to at least partially enclose the first and second housings 102,104 therein. The first shell element 132 may define an interior openingor cavity sized and shaped to receive at least a portion of the firsthousing 102 therein, and the second shell element 134 may define aninterior opening or cavity sized and shaped to receive at least aportion of the second housing 104 therein. In the illustrated example,the first and second shell elements 132, 134 define substantially hollowcylindrical bodies positionable around substantially cylindricalexterior surfaces of the first and second housings 102, 104. Alternativevariations in shapes and sizes may be implemented to accommodate varyingprosthesis shapes.

The first and second shell elements may be constructed from a materialhaving stronger and/or less pliable properties compared to that of thefirst and second housings to reduce or eliminate expansion, separation,and/or deformation of the first and second housings when the assembly100 is used to manufacture a prosthesis. For example, the first andsecond shell elements may be constructed from one or more metals,polymers, or otherwise, and/or may have a durometer or hardness betweenShore 40D and 80D.

The first and second housings 102, 104 may define one or more featuresfacilitating alignment and/or prevention of rotation or unwanteddisplacement when secured inside of the first and second shell elements132, 134. For example, each of the first and second housings may defineone or more grooves 136 a, 136 b respectively, extending along ordefined within an exterior surface of the housings. The grooves 136 a,136 b may extend along the longitudinal length of the housings, andalign with and receive a portion of respectively complementaryprotruding ribs 138 a, 138 b on interior surfaces of the first andsecond shell elements. When the first and second housings are positionedwithin the first and second shell elements, the aligned grooves 136 a,136 b and ribs 138 a, 138 b restrict rotational movement of the housingswith respect to the shell elements when the components of the assembly100 are engaged and assembled to one another.

The femoral mold assembly 100 may include one or more connectingelements 140 to releasably secure the first shell element 132 to thesecond shell element 134. In the illustrated example, the connectingelement 140 includes a threaded lock ring that engages threaded segmentsof both the first and second shell elements to secure the componentstogether, thereby providing added rigidity and resistance to expansionor separation of the first and second shell elements, and thus the firstand second housings contained therein when the assembly 100 is used tomanufacture a prosthesis. Other examples of suitable connecting elementsmay include one or more clasps, fasteners, or other releasablyengageable mechanisms.

Now turning to FIGS. 8-15, another example of an orthopedic prosthesismold assembly 200 is shown that may be used to manufacture tibial-kneeprostheses. The tibial mold assembly 200 may include features andcharacteristics similar to the mold assembly 100 and other featuresdescribed herein. The mold assembly 200 generally includes a firsthousing or body 202 and a second housing or body 204 releasablyengageable with the first housing. The first and second housings definecavities therein sized and shaped to produce an orthopedic prosthesis,such as that of a tibial knee joint component. For example, the firsthousing 202 may define or include a first cavity 206 therein forreceiving a curable material to be formed or shaped into at least aportion of an orthopedic prosthesis. The second housing 204 may includea second cavity 208 for receiving a curable material to be formed orshaped into at least a portion of an orthopedic prosthesis. The secondcavity 208 may be positional adjacent to and/or substantially congruouswith the first cavity 206 when the first and second housings are engagedor coupled to one another to cooperatively from a substantiallycontinuous prosthesis.

The mold assembly 200 may include a height-adjustable assembly ofcomponents that enables a physician to modify or select the resultingheight of a prosthesis manufactured with the Assembly 200 to accommodatea range of varying anatomical dimensions of varying patients. Forexample, the assembly 200 may include a prosthesis mold insert 242 thatis removably positionable within the cavity 208 of the second housing204. The insert 242 may define one or more surface features configuredto produce a resulting prosthesis with the desired contours and featuresfor the particular anatomy at issue, in this example being a tibial kneecomponent. The mold assembly 200 may also include one or more spacingelements 24 removably positionable within the cavity 208 of the secondhousing 204 that can be used to adjust the resulting depth or height ofthe cavity 208 that is filled with curable material. The spacingelement(s) 244 may have a cross-sectional shape similar to that of thecavity 208, allowing multiple spacing element(s) 244 to be positionedinto the cavity 108 underneath the mold insert 242 and thus adjust theopen space in the cavity between the mold insert 242 and the top of thecavity 206 of the first housing. For example, to manufacture aprosthesis with a larger height, fewer spacing elements 244 would beinserted into the cavity 208, thereby allowing a larger mold spacetherein to be filled with curable molding material. As a result, aphysician can select the quantity of spacing elements to insert into thecavity 208, thereby adjusting the relative height or distance of themold space, and thus selecting and controlling the particular height ofthe molded prosthesis.

In an alternative to selecting a quantity of spacing elements to achievethe desired prosthesis height, a plurality of spacing elements 244 maybe provided that each have a different height from the others, whichallows a physician to select a single spacing element with the desiredresulting height offset within the cavity 208. In another alternativeexample, a plurality of second housings 204 may be provided, with eachof the plurality of second housings having a different depth ordimensioned cavity 208 compared to others of the plurality. In thisexample, a physician would select the housing 204 with the desired depthor height of the cavity 208 to create a prosthesis having the desiredsize.

The first and second housings 202, 204 may define one or more grooves,detents, lips, or other mating features complimentary to each other toaid in aligning and/or securing the components to one another, and tofurther resist separation when under pressure from injection of materialinto the mold and/or expansion or curing of an injected material. Thesecond housing 204 may include or define a recessed groove 222circumscribing or otherwise routing along the interior cavity 208, withthe first housing 202 defining a complementary wall or protruding rib224 circumscribing or otherwise routing around the interior cavity 206that is securable in the groove 222. Providing such matable lock-and-keyfeatures provides increased resistance to separation between thehousings, as well as reducing the likelihood of leakage at the couplingpoints between the first and second housings.

The first housing 202 may define an injection opening 226 incommunication with the interior cavity 206 to allow the first and secondhousings 202, 204 to be filled with a curable material to form aprosthesis. An injection opening cap or cover 228 may also be included.The injection opening cap 228 may include a stamping component orindicia that imprints one or more indicia onto the injected moldingmaterial within the first and second cavities prior to curing. Theinjection cap 228 may further include a cutting surface or edge toremove, debride, or otherwise remove excess portions of the moldedprosthesis once its cured. The first housing 202 may further define oneor more vents 230 in an upper surface thereof to allow air pockets toescape, as well as provide an exit or spillway for excess material.

Similar to that of the assembly 100, the first and second housings 202,204 of the assembly 200 may be constructed from a polymer including oneor more rubber or silicone components, and may have a durometer orhardness between Shore 40A to 80A. The first and second housings mayprovide a desired degree of pliability to facilitate removing a moldedprosthesis from the interior cavities of the first and second housings.

The mold assembly 200 may include an exterior casing or shell that isreleasably engageable to, and at least partially encompassing of, thefirst and second housings 202, 204 to secure the overall assembly andposition of the first and second housings relative to one another duringuse. For example, the assembly 200 may include a first shell element 232and a second shell element 234 that are releasably engageable to oneanother to at least partially enclose the first and second housings 202,204 therein. The first shell element 232 may define an interior openingor cavity sized and shaped to receive at least a portion of the firsthousing 202 therein, and the second shell element 234 may define aninterior opening or cavity sized and shaped to receive at least aportion of the second housing 204 therein. In the illustrated example,the first and second shell elements 232, 234 define substantially hollowcylindrical bodies positionable around substantially cylindricalexterior surfaces of the first and second housings 202, 204. Alternativevariations in shapes and sizes may be implemented to accommodate varyingprosthesis shapes.

The first and second shell elements 232, 234 may be constructed from amaterial having stronger and/or less pliable properties compared to thatof the first and second housings to reduce or eliminate expansion,separation, and/or deformation of the first and second housings when theassembly 200 is used to manufacture a prosthesis. For example, the firstand second shell elements may be constructed from one or more metals,polymers, or otherwise, and/or may have a durometer or hardness betweenShore 40D and 80D.

The first and second housings 202, 204 may define one or more featuresfacilitating alignment and/or prevention of rotation or unwanteddisplacement when secured inside of the first and second shell elements232, 234. For example, each of the first and second housings may defineone or more grooves 236 a, 236 b respectively, extending along ordefined within an exterior surface of the housings. The grooves 236 a,236 b may extend along the longitudinal length of the housings, andalign with and receive a portion of respectively complementaryprotruding ribs 238 a, 238 b on interior surfaces of the first andsecond shell elements. When the first and second housings are positionedwithin the first and second shell elements, the aligned grooves 236 a,236 b and ribs 238 a, 238 b restrict rotational movement of the housingswith respect to the shell elements when the components of the assembly200 are engaged and assembled to one another.

The tibial mold assembly 200 may include one or more connecting elements240 to releasably secure the first shell element 232 to the second shellelement 234. In the illustrated example, the connecting element 240includes a threaded lock ring that engages threaded segments of both thefirst and second shell elements to secure the components together,thereby providing added rigidity and resistance to expansion orseparation of the first and second shell elements, and thus the firstand second housings contained therein when the assembly 200 is used tomanufacture a prosthesis. Other examples of suitable connecting elementsmay include one or more clasps, fasteners, or other releasablyengageable mechanisms.

Now turning to FIGS. 16-21, another example of an orthopedic prosthesismold assembly 300 is shown that may be used to manufacture hip headprostheses. The hip head mold assembly 300 may include features andcharacteristics similar to the mold assemblies 100, 200 and otherfeatures described herein. The mold assembly 300 generally includes afirst housing or body 302 and a second housing or body 304 releasablyengageable with the first housing. The first and second housings definecavities therein sized and shaped to produce an orthopedic prosthesis,such as that of a hip head joint component. For example, the firsthousing 302 may define or include a first cavity 306 therein forreceiving a curable material to be formed or shaped into at least aportion of an orthopedic prosthesis. The second housing 304 may includea second cavity 308 for receiving a curable material to be formed orshaped into at least a portion of an orthopedic prosthesis. The secondcavity 308 may be positional adjacent to and/or substantially congruouswith the first cavity 306 when the first and second housings are engagedor coupled to one another to cooperatively from a substantiallycontinuous prosthesis.

The mold assembly 300 may include a prosthesis insert 342 that isremovably positionable within the cavity 306 of the first housing 302that forms a part of the manufactured hip head prosthesis. For example,the insert 342 may include a socket or plug that is molded into thecured prosthesis to later receive a portion of a hip or femur stemimplant component, such as the trunnion. As shown in FIG. 19, the insert342 may releasably engage with a protrusion or other matable feature onan underside of the first housing 302 in a desired position with respectto the injected molding material and overall shape imparted by the moldassembly 300. In another example as shown in FIG. 17b , the insert 342may engage with a pin 343 that is removably positionable through anopening in the first housing 302 to secure the insert in the desiredposition within the cavity 306. The attachment/engagement between thepin 343 and the insert 342 may be accomplished through a friction fit,temporary adhesive, or other releasable mechanisms.

The first and second housings 302, 304 may define one or more grooves,detents, lips, or other mating features complimentary to each other toaid in aligning and/or securing the components to one another, and tofurther resist separation when under pressure from injection of materialinto the mold and/or expansion or curing of an injected material. Thesecond housing 304 may include or define a recessed groove 322circumscribing or otherwise routing along the interior cavity 308, withthe first housing 302 defining a complementary wall or protruding rib324 circumscribing or otherwise routing around the interior cavity 306that is securable in the groove 322. Providing such matable lock-and-keyfeatures provides increased resistance to separation between thehousings, as well as reducing the likelihood of leakage at the couplingpoints between the first and second housings.

The first housing 302 may define an injection opening 326 incommunication with the interior cavity 306 to allow the first and secondhousings 302, 304 to be filled with a curable material to form aprosthesis. An injection opening cap or cover 328 may also be included.The injection opening cap 328 may include a stamping component orindicia that imprints one or more indicia onto the injected moldingmaterial within the first and second cavities prior to curing. Theinjection cap 328 may further include a cutting surface or edge toremove, debride, or otherwise remove excess portions of the moldedprosthesis once its cured. The first housing 302 may further define oneor more vents 330 in an upper surface thereof to allow air pockets toescape, as well as provide an exit or spillway for excess material.

Similar to that of the assemblies described above, the first and secondhousings 302, 304 of the assembly 300 may be constructed from a polymerincluding one or more rubber or silicone components, and may have adurometer or hardness between Shore 40A and 80A. The first and secondhousings may provide a desired degree of pliability to facilitateremoving a molded prosthesis from the interior cavities of the first andsecond housings.

The mold assembly 300 may include an exterior casing or shell that isreleasably engageable to, and at least partially encompassing of, thefirst and second housings 302, 304 to secure the overall assembly andposition of the first and second housings relative to one another duringuse. For example, the assembly 300 may include a first shell element 332and a second shell element 334 that are releasably engageable to oneanother to at least partially enclose the first and second housings 302,304 therein. The first shell element 332 may define an interior openingor cavity sized and shaped to receive at least a portion of the firsthousing 302 therein, and the second shell element 334 may define aninterior opening or cavity sized and shaped to receive at least aportion of the second housing 304 therein. In the illustrated example,the first and second shell elements 332, 334 define substantially hollowcylindrical bodies positionable around substantially cylindricalexterior surfaces of the first and second housings 302, 304. Alternativevariations in shapes and sizes may be implemented to accommodate varyingprosthesis shapes.

The first and second shell elements 332, 334 may be constructed from amaterial having stronger and/or less pliable properties compared to thatof the first and second housings to reduce or eliminate expansion,separation, and/or deformation of the first and second housings when theassembly 200 is used to manufacture a prosthesis. For example, the firstand second shell elements may be constructed from one or more metals,polymers, or otherwise, and/or may have a durometer or hardness betweenShore 40D and 80D.

The first and second housings 302, 304 may define one or more featuresfacilitating alignment and/or prevention of rotation or unwanteddisplacement when secured inside of the first and second shell elements332, 334. For example, each of the first and second housings may defineone or more grooves 336 a, 336 b respectively, extending along ordefined within an exterior surface of the housings. The grooves 336 a,336 b may extend along the longitudinal length of the housings, andalign with and receive a portion of respectively complementaryprotruding ribs 338 a, 338 b on interior surfaces of the first andsecond shell elements. When the first and second housings are positionedwithin the first and second shell elements, the aligned grooves 336 a,336 b and ribs 338 a, 338 b restrict rotational movement of the housingswith respect to the shell elements when the components of the assembly300 are engaged and assembled to one another.

The mold assembly 300 may include one or more connecting elements 340 toreleasably secure the first shell element 332 to the second shellelement 334. In the illustrated example, the connecting element 340includes a threaded lock ring that engages threaded segments of both thefirst and second shell elements to secure the components together,thereby providing added rigidity and resistance to expansion orseparation of the first and second shell elements, and thus the firstand second housings contained therein when the assembly 300 is used tomanufacture a prosthesis. Other examples of suitable connecting elementsmay include one or more clasps, fasteners, or other releasablyengageable mechanisms.

Now turning to FIGS. 22-25, another example of an orthopedic prosthesismold assembly 400 is shown that may be used to manufacture hip orfemoral stem prostheses. The hip stem mold assembly 400 may includefeatures and characteristics similar to the mold assemblies 100, 200,300 and other features described herein. The mold assembly 400 generallyincludes a first housing or body 402 and a second housing or body 404releasably engageable with the first housing. The first and secondhousings define cavities therein sized and shaped to produce anorthopedic prosthesis, such as that of a hip head joint component. Forexample, the first housing 402 may define or include a first cavity 406therein for receiving a curable material to be formed or shaped into atleast a portion of an orthopedic prosthesis. The second housing 404 mayinclude a second cavity 408 for receiving a curable material to beformed or shaped into at least a portion of an orthopedic prosthesis.The second cavity 408 may be positional adjacent to and/or substantiallycongruous with the first cavity 406 when the first and second housingsare engaged or coupled to one another to cooperatively from asubstantially continuous prosthesis.

The mold assembly 400 may include a prosthesis insert 442 that isremovably positionable within the cavity 306 of the first housing 302that forms a part of the manufactured hip stem prosthesis. For example,the insert 442 may include a metallic femur or hip stem that is at leastpartially encased within the molded, cured prosthesis, as shown in FIG.23.

In another example as shown in FIG. 26, the insert 442 may define orinclude a porous lattice structure in the body of the stem insert toallow for the fenestration of PMMA and/or other mold materials in andaround the insert 442. The porous structure may include one or moreholes, cavities, honeycomb constructs, and/or other features machined,drilled, 3D printed, or otherwise implemented into a segment of theinsert 442. This porous structure allows for numerous advantages,including but not limited to improved polymer, prosthesis, antibiotic,an/or biologic material attachment to the insert 442, which can mitigatedelamination, fracture, or other failures of the prosthesis. Suchlattice or honeycomb structure may be applied to different orthopedicinserts, such as those described herein for various arm, leg, knee orother joints.

The first and second housings 402, 404 may define one or more grooves,detents, lips, or other mating features complimentary to each other toaid in aligning and/or securing the components to one another, and tofurther resist separation when under pressure from injection of materialinto the mold and/or expansion or curing of an injected material. Thesecond housing 404 may include or define a recessed groove 422circumscribing or otherwise routing along the interior cavity 408, withthe first housing 402 defining a complementary wall or protruding rib424 circumscribing or otherwise routing around the interior cavity 406that is securable in the groove 422. Providing such matable lock-and-keyfeatures provides increased resistance to separation between thehousings, as well as reducing the likelihood of leakage at the couplingpoints between the first and second housings.

The first housing 402 may define an injection opening 426 incommunication with the interior cavity 406 to allow the first and secondhousings 402, 404 to be filled with a curable material to form aprosthesis. An injection opening cap or cover 428 may also be included.The injection opening cap 428 may include a stamping component orindicia that imprints one or more indicia onto the injected moldingmaterial within the first and second cavities prior to curing. Theinjection cap 428 may further include a cutting surface or edge toremove, debride, or otherwise remove excess portions of the moldedprosthesis once its cured. The first housing 402 may further define oneor more vents 430 in a surface thereof to allow air pockets to escape,as well as provide an exit or spillway for excess material. A vent plugor cap 444 may be included to removably cover the vent 430.

Similar to that of the assemblies described above, the first and secondhousings 402, 404 of the assembly 400 may be constructed from a polymerincluding one or more rubber or silicone components, and may have adurometer or hardness between Shore 40A and 80A. The first and secondhousings may provide a desired degree of pliability to facilitateremoving a molded prosthesis from the interior cavities of the first andsecond housings.

The mold assembly 400 may include an exterior casing or shell that isreleasably engageable to, and at least partially encompassing of, thefirst and second housings 402, 404 to secure the overall assembly andposition of the first and second housings relative to one another duringuse. For example, the assembly 400 may include a first shell element 432and a second shell element 434 that are releasably engageable to oneanother to at least partially enclose the first and second housings 402,404 therein. The first shell element 432 may define an interior openingor cavity sized and shaped to receive at least a portion of the firsthousing 402 therein, and the second shell element 434 may define aninterior opening or cavity sized and shaped to receive at least aportion of the second housing 404 therein.

The first and second shell elements 432, 434 may be constructed from amaterial having stronger and/or less pliable properties compared to thatof the first and second housings to reduce or eliminate expansion,separation, and/or deformation of the first and second housings when theassembly 400 is used to manufacture a prosthesis. For example, the firstand second shell elements may be constructed from one or more metals,polymers, or otherwise, and/or may have a durometer or hardness betweenShore 40D and 80D.

The mold assembly 400 may include one or more connecting elements 440 toreleasably secure the first shell element 432 to the second shellelement 434. In the illustrated example, the connecting element 440includes a threaded lock ring that engages threaded segments of both thefirst and second shell elements to secure the components together,thereby providing added rigidity and resistance to expansion orseparation of the first and second shell elements, and thus the firstand second housings contained therein when the assembly 400 is used tomanufacture a prosthesis. Other examples of suitable connecting elementsmay include one or more clasps, fasteners, or other releasablyengageable mechanisms.

For any of the assemblies disclosed herein, the first and secondshousings may be encased or reinforced by the exterior shell elementsalong differing axes or planes of attachment and alignment to furthersecure the assemblies together under the significant expansion pressuresexperienced by the mold when a curable material, such as PMMA orotherwise, is used to create a prosthesis. For example, as shown in FIG.23, the first and second housings 402, 404 align and attach to eachother (via the complementary wall and groove features, or as otherwisedescribed herein) along a first axis 450. The first and second shellelements 432, 434 align and attach to each other along a second axis 452that is not parallel to the first axis. The second axis may, forexample, form an angle between 45 degrees and 135 degrees with the firstaxis. As a result, when the assembly 400 is assembled and curablemolding material is injected into the inner cavities 406, 408 of thefirst and second housing 402, 404 respectively, the outward expansionpressure of the curable material will exert outward to attempt toseparate the first and second housings 402, 404 where they join, i.e.,generally along the axis 450. However, the first and second shellelements 423, 434 do not have a seam or joint along the axis 450(instead joining and attaching along the second axis 452), and thusprovide a uniform internal surface in the direction that the first andsecond housings 402, 404 join to one another. The expansion forcesexperienced within the cavities 406, 408 are thus directed uniformlythroughout the cavities without separation of the first and secondhousings 402, 404 to provide a substantially uniform molded prosthesis.

The assemblies disclosed herein may include or otherwise be combinedwith additional components in a kit or system allowing a physician tomodify, adjust, and/or otherwise conform a molded prosthesis to aspecific patient. For example, as shown in FIG. 27, the molded steminsert 442 may be coupled to a molded hip head or acetabular cup 500(which may be constructed using the molds and assemblies describedherein). The relative height or position of the head 500 on the stem maybe selectively adjustable by using one or more sleeves 502 a, 502 b, . .. (collectively referred to as ‘502’) having varying heights. Thephysician may select the sleeve 502 having the height and dimensionsproviding the desired offset or positioning of the head 500 for theparticular anatomy of a patient being addressed. Multiple sleeves havingvarying dimensions may be provided as a kit or system accompanying themold assemblies described herein.

It will be appreciated by persons skilled in the art that the presentdisclosure is not limited to what has been particularly shown anddescribed herein above. In addition, unless mention was made above tothe contrary, it should be noted that all of the accompanying drawingsare not to scale. Of note, the system components have been representedwhere appropriate by conventional symbols in the drawings, showing onlythose specific details that are pertinent to understanding theembodiments of the present disclosure so as not to obscure thedisclosure with details that will be readily apparent to those ofordinary skill in the art having the benefit of the description herein.Moreover, while certain embodiments or figures described herein mayillustrate features not expressly indicated on other figures orembodiments, it is understood that the features and components of theexamples disclosed herein are not necessarily exclusive of each otherand may be included in a variety of different combinations orconfigurations without departing from the scope and spirit of thedisclosure. A variety of modifications and variations are possible inlight of the above teachings without departing from the scope and spiritof the disclosure, which is limited only by the following claims.

What is claimed is:
 1. An orthopedic prosthesis mold system, comprising:a first housing including a first cavity therein shaped to form aportion of a tibial knee joint prosthesis; a second housing coupled tothe first housing, the second housing including a second cavity thereinshaped to form a portion of a tibial knee joint prosthesis; a pluralityof spacing elements positionable within the second cavity of the secondhousing configured to selectively adjust a height of a prosthesis moldedtherein; a first shell element configured to receive at least a portionof the first housing therein; a second shell element configured toreceive at least a portion of the first housing therein; and aconnection element releasably engageable to the first and second shellelements to prevent separation of the first shell element from thesecond shell element.
 2. The orthopedic prosthesis mold system of claim1, further comprising a mold insert positionable within the secondcavity of the second housing, wherein the mold insert has a tibialcondylar shape.
 3. The orthopedic prosthesis mold system of claim 2,wherein the plurality of spacing elements are positionable within thesecond cavity of the second housing to adjust the location of the moldinsert within the second cavity.
 4. The orthopedic prosthesis moldsystem of claim 1, wherein the first and second housings are constructedfrom a material having a first hardness, and wherein the first andsecond shell elements are constructed from a material having a secondhardness greater than the first hardness.
 5. The orthopedic prosthesismold system of claim 1, wherein the first and second housings areconstructed from a material having a hardness between Shore 40A and 80A.6. The orthopedic prosthesis mold system of claim 1, wherein the firstand second shell elements are constructed from a material having ahardness between Shore 40D and 80D.
 7. The orthopedic prosthesis moldsystem of claim 1, wherein the first and second housings align with andattach to one another along a first axis, and wherein the first andsecond shell elements align with and attach to one another along asecond axis that is not parallel to the first axis.
 8. The orthopedicprosthesis mold system of claim 1, wherein the first housing defines aninjection port.
 9. The orthopedic prosthesis mold system of claim 8,further comprising an injection port cap releasably engageable with theinjection port to seal the injection port.
 10. The orthopedic prosthesismold system of claim 1, wherein the first and second shell elements aresubstantially cylindrical.
 11. The orthopedic prosthesis mold system ofclaim 1, wherein the first housing defines a groove circumscribing thefirst cavity; and wherein the second housing defines a protruding wallcircumscribing the second cavity, the wall being insertable into thegroove.
 12. The orthopedic prosthesis mold system of claim 1, whereinthe first and second housings each define one or more longitudinalgrooves in exterior surfaces thereof, wherein the first and second shellelements each define one or more protruding ribs on interior surfacesthereof, and wherein the protruding ribs are positionable in thelongitudinal grooves.
 13. An orthopedic prosthesis mold system,comprising: a first housing including a first cavity therein shaped toform a portion of a hip stem prosthesis; a second housing coupled to thefirst housing, the second housing including a second cavity thereinshaped to form a portion of a hip stem prosthesis; a first shell elementconfigured to receive at least a portion of the first housing therein; asecond shell element configured to receive at least a portion of thefirst housing therein; and a connection element releasably engageable tothe first and second shell elements to prevent separation of the firstshell element from the second shell element.
 14. The orthopedicprosthesis mold system of claim 13, further comprising a stem insertpositionable within the second cavity of the second housing, wherein thestem insert defines a porous lattice structure in a portion thereof. 15.The orthopedic prosthesis mold system of claim 13, wherein the first andsecond housings are constructed from a material having a first hardness,and wherein the first and second shell elements are constructed from amaterial having a second hardness greater than the first hardness. 16.The orthopedic prosthesis mold system of claim 13, wherein the first andsecond housings align with and attach to one another along a first axis,and wherein the first and second shell elements align with and attach toone another along a second axis that is not parallel to the first axis.17. The orthopedic prosthesis mold system of claim 13, wherein the firsthousing defines an injection port.
 18. The orthopedic prosthesis moldsystem of claim 17, further comprising an injection port cap releasablyengageable with the injection port to seal the injection port.
 19. Theorthopedic prosthesis mold system of claim 13, wherein the first housingdefines a groove circumscribing the first cavity; and wherein the secondhousing defines a protruding wall circumscribing the second cavity, thewall being insertable into the groove.
 20. The orthopedic prosthesismold of claim 13, wherein the connection element includes a threadedlock ring engaging circumferentially threaded segments of the first andsecond shell elements.